remove mysql wrapper
move docs to directory docs
add pgsql wrapper and nst lib
a new version begin

* all new recode
* drop mysql wrapper and change to pgsql wrapper
* master/slave all in one, but need select mode in config page
* multiplexing nst_lib common library
update thanks
update default dbhost setting
== re-structure This EA ==

* all new structure
* add mode setting: master / slave / test / monitor(if need)
Merge commit '9c9e530b2ef4d76d447d1ebbf8433b337c812517'